Self contained humidity control system for forced air duct system

ABSTRACT

A fully self contained, in-line humidity control system for a forced air HVAC system. The system is designed to be integrated into the duct system of an existing or new installation forced air HVAC system such that the environment throughout a structure may be dehumidified by a central system. Optional electric heating elements may be included, in addition to the evaporator and condenser, to provide additional dehumidification. The system may be freestanding for structures not having a forced air HVAC system. A freestanding system may optionally be ducted, space permitting to provide the benefits of the in-line system in a structure not having a central, forced air HVAC system.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to humidity control equipment for forced air ventilation and air conditioning (HVAC) systems. More particularly, the invention comprises an in-line humidity control system which may be fit, as a unit, into the duct system of an HVAC system. An optional heating element may be included in the system for use in severe moisture conditions.

2. Description of the Prior Art

Humidity control within a building is of utmost importance from both a comfort standpoint for the occupants and the preservation of the building and items within the building.

U.S. Pat. No. 6,623,550, issued to Shah, et al., on Sep. 23, 2003, discloses an APPARATUS FOR CONTROLLING AIR QUALITY, wherein a first air stream is conditioned and circulated to an interior space and a second air stream is treated and circulated to an exterior space. The second air stream is, preferably, heated such that moisture is removed from the first air stream by a desiccant. By contrast, the present invention utilizes only a single air stream.

In U.S. Pat. No. 6,622,508, issued on Sep. 23, 2003, to Dinnage, et al., a METHOD FOR HEAT AND HUMIDITY EXCHANGE BETWEEN TWO AIR STREAMS AND APPARATUS THEREFOR is disclosed. A first air stream is transferred from the interior of a building through a heat exchanger, heater and dehumidifier before being discharged to the ambient air. A second air stream is passed through the dehumidifier and heat exchanger, before passing through a cooling device before being transferred to the interior of the building. Again, by contrast, the present invention relies on only a single air stream.

Piao, et al., disclose an AIR CONDITIONING SYSTEM in U.S. Pat. No. 6,619,064, issued on Sep. 16, 2003. Ambient air is taken into a first air stream passing through a compressor, heat exchanger and expander before being discharged into an interior space. In a second air stream, interior air is conducted to the exterior. Moisture is withdrawn from the first air stream by a dehumidifier and released back to the exterior via the second air stream. Again, Riao, et al., rely on two air streams, as opposed to the single air stream of the present invention.

An AIR HANDLER WITH RETURN AIR BYPASS FOR IMPROVED DEHUMIDIFICATION is disclosed in U.S. Pat. No. 6,604,688, issued to Ganesh, et al., on Aug. 12, 2003, wherein a portion of the return air bypasses the cooling coil of a variable air volume (VAB) system, thereby returning a portion of relatively warm, dry air downstream of the coil. By contrast, the present invention directs all of the return air through the in-line humidity control system.

None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.

SUMMARY OF THE INVENTION

The present invention provides a humidity control system which may be fit, as a unit, into the duct system of an HVAC system. The system utilizes the conventional elements of compressor, evaporator and condenser to dehumidify the air passing therethrough, with a humidistat determining when operation is necessary and controlling an on/off switch for the unit. An optional heating element within the system may be used to provide additional dehumidification in extreme moisture environments.

Accordingly, it is a principal object of the invention to provide an in-line humidity control unit for an HVAC system.

It is another object of the invention to provide an in-line humidity control unit which can be installed, as a unit, in the duct system of an HVAC system.

It is a further object of the invention to provide an in-line humidity control system which may be easily installed into the duct system of an existing HVAC system or into a new HVAC installation.

Still another object of the invention is to provide an in-line humidity control system which is self controlling.

An additional object of the invention is to provide an in-line humidity control system which may provide additional dehumidification and/or room heating via heating elements contained within the unit.

It is again an object of the invention to provide a humidity control system which may be operated as a free standing unit, separate from a forced air HVAC system.

Yet another object of the invention is to provide a humidity control system which is compact enough that it may be installed in areas of limited space, such as a crawl space.

It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.

These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:

FIG. 1 is a diagrammatic view of the in-line humidity control system of the present invention with a drain pan internal of the system and gravity feed drain line.

FIG. 2 is a diagrammatic view of the in-line humidity control system of the present invention with a drain pan internal of the system and a pump driven drain line.

FIG. 3 is a diagrammatic view of the in-line humidity control system of the present invention with a drain pan external of the system with either a gravity feed or pump driven drain line (both shown, although only one would be utilized).

FIG. 4 is a diagrammatic view of a free standing humidity control system, independent of a forced air HVAC system or ducts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1 through 3, as in most humidity control units, the in-line humidity control unit 1 of the present invention consists, essentially, of a fan 20, compressor 30, evaporator 40, condenser 50, and humidistat 60, all contained within a housing 10 which is adapted to be fit into supply duct line 100 of a forced air HVAC system (not shown). The individual elements or the fan 20, compressor 30, evaporator 40, condenser 50 and humidistat 60 are not deemed to be inventive, in and of themselves, and will not be individually described in further detail. It would be evident to one of ordinary skill in the art that the fan of the HVAC system could be used in lieu of the fan 20 of the present invention.

The humidistat 60 of the present system 1 may be either of two basic types. It may be permanently set at a determined humidity level or variably set to a user determined humidity level. The humidistat 60 determines the level of suspended moisture in the air being conditioned and whether the system 1 needs to be operating or not. The humidistat 60 situated proximate the system 1 or remotely therefrom, and likewise, may be controlled by a sensor (not shown) within or attached to the system 1 or remote therefrom, depending on the environment in which the system 1 is being used.

As the humidistat 60 calls for dehumidification, the compressor 30 is activated and the fan 10 moves air across the coils of the evaporator 40 such that moisture carried in the air condenses onto the coils of the evaporator 40 and drains to a catch pan 52. Condensate in catch pan 52 may, optionally, be drained by gravity feed through a drain tube 56 (FIG. 1), or discharged via a pump 54 through drain tube 56 (FIG. 2). It would be evident to one of ordinary skill in the art that pump 54 could be at the end of drain tube 56 proximate catch pan 52 or at a distal end thereof (not shown). It would be further evident that in lieu of a catch pan 52 within the system 1, the condensate could be funneled directly from the evaporator 40 to the drain tube 56 (FIG. 3) and to a remote catch pan 52. From the remote catch pan 52, condensate may be drained by gravity through a drain tube 56 a or by pump 54 to a drain tube 56 b (FIG. 3 (both shown, although only one would be utilized)) to an external point or drain (not shown).

Optionally, electric heating elements 70 my be included in the system 1 to aid in dehumidification in extreme moisture environments, the heat generated by the heating elements 70 (Fi. 3) causing further evaporation of moisture left after the air has passed over the evaporator 40 and condenser 50.

The housing 10 of the system 1 may be incorporated into the duct system of the HVAC system, usually between a main supply duct 100 and the branches of the distribution ducts 110.

It would be evident to one of ordinary skill in the art that while the system 1 a of the present invention is primarily intended to be installed into the supply duct 100 of a forced air HVAC system, the system 1 could be installed independent of an HVAC system, and without ducts 100/110, for single room dehumidification (FIG. 4), or, space permitting, with ducts 100/110 in the case of a non-forced air heating system (FIG. 1-3), for dehumidification of an area beyond the immediate environs of the system 1. In this free standing system 1 a, not associated with a forced air heating system, the heating elements 70 may also be used to provide heated air to the environment being dehumidified.

It would be evident to one of ordinary skill in the art that the system 1 could be variously configured to meet the dehumidification needs and space constraints of differing applications, including the sizing of the compressor 30 and evaporator 40, and the physical arrangement of the housing 10.

It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. 

1. An in-line humidity control system for a forced air HVAC system comprising: system components comprising: air movement means for moving air through said humidity control system, compressor means for chilling refrigerant circulating within said humidity control system, evaporator means for removing suspended moisture from air passing through said humidity control system, condenser means for condensing a refrigerant for flow through said evaporator, and collection means for collecting moisture condensed by said evaporator, draining means for draining said collected condensate from said humidity control system, and control means for determining the amount of suspended moisture in the air being moved and controlling the operation of said humidity control system, and housing means for enclosing at least some of said components of said humidity control system and for forming a segment of a duct system.
 2. An in-line humidity control system for a forced air HVAC system, as defined in claim 1, wherein said air movement means comprises one from the group consisting of the fan of said forced air system to which the humidity control system is connected and a fan located within said housing means of said humidity control system.
 3. An in-line humidity control system for a forced air HVAC system, as defined in claim 1, wherein said collection means comprises a drain line extending from said humidity control system to a drain exiting the building in which said system is installed in combination with one from the group consisting of a collection pan within said housing means and a collection pan exterior of said housing means.
 4. An in-line humidity control system for a forced air HVAC system, as defined in claim 1, wherein said draining means comprises one from the group consisting of a gravity feed drain line and a discharge pump.
 5. An in-line humidity control system for a forced air HVAC system, as defined in claim 1, wherein said control means comprises a humidistat.
 6. An in-line humidity control system for a forced air HVAC system, as defined in claim 1, further comprising electrical heating elements, said electrical heating elements providing additional evaporation of moisture from air having already passed through said evaporator and condenser.
 7. A humidity control system comprising: system components comprising: air movement means for moving air through said humidity control system, compressor means for chilling refrigerant circulating within said humidity control system, evaporator means for removing suspended moisture from the air passing through said humidity control system, condenser means for condensing a refrigerant for flow through said evaporator, and collection means for collecting moisture condensed by said condenser, draining means for draining said collected condensate from said humidity control system, and control means for determining the amount of suspended moisture in the air being moved and controlling the operation of said humidity control system, and housing means for enclosing at least some of said components of said humidity control system.
 8. A humidity control system, as defined in claim 7, wherein said air movement means comprises a fan.
 9. A humidity control system, as defined in claim 7, wherein said collection means comprises a drain line extending from said humidity control system to a drain exiting the building in which said system is installed in combination with one from the group consisting of a collection pan within said housing means and a collection pan exterior of said housing means.
 10. A humidity control system, as defined in claim 7, wherein said draining means comprises one from the group consisting of a gravity feed drain line and a discharge pump.
 11. A humidity control system, as defined in claim 7, wherein said control means comprises a humidistat.
 12. A humidity control system, as defined in claim 7, further comprising electrical heating elements, said electrical heating elements providing at least one function from the group comprising: additional evaporation of moisture from air having already passed through said evaporator and condenser, and heated air to the environment being dehumidified.
 13. A humidity control system, as defined in claim 7, further comprising ducts extending from said housing means such that dehumidified air may be collected from and distributed beyond the immediate environs of said system. 